1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "att_server.c" 39 40 41 // 42 // ATT Server Globals 43 // 44 45 #include <stdint.h> 46 #include <string.h> 47 #include <inttypes.h> 48 49 #include "btstack_config.h" 50 51 #include "ble/att_dispatch.h" 52 #include "ble/att_db.h" 53 #include "ble/att_server.h" 54 #include "ble/core.h" 55 #include "ble/le_device_db.h" 56 #include "ble/sm.h" 57 #include "bluetooth_psm.h" 58 #include "btstack_debug.h" 59 #include "btstack_event.h" 60 #include "btstack_memory.h" 61 #include "btstack_run_loop.h" 62 #include "gap.h" 63 #include "hci_dump.h" 64 #include "l2cap.h" 65 #include "btstack_tlv.h" 66 #ifdef ENABLE_LE_SIGNED_WRITE 67 #include "ble/sm.h" 68 #include "bluetooth_psm.h" 69 70 #endif 71 72 #ifdef ENABLE_TESTING_SUPPORT 73 #include <stdio.h> 74 #endif 75 76 #ifndef NVN_NUM_GATT_SERVER_CCC 77 #define NVN_NUM_GATT_SERVER_CCC 20 78 #endif 79 80 #define ATT_SERVICE_FLAGS_DELAYED_RESPONSE (1<<0u) 81 82 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection); 83 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle); 84 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle); 85 static void att_server_handle_can_send_now(void); 86 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection); 87 static void att_server_persistent_ccc_clear(att_server_t * att_server); 88 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size); 89 90 typedef enum { 91 ATT_SERVER_RUN_PHASE_1_REQUESTS = 0, 92 ATT_SERVER_RUN_PHASE_2_INDICATIONS, 93 ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS, 94 } att_server_run_phase_t; 95 96 // 97 typedef struct { 98 uint32_t seq_nr; 99 uint16_t att_handle; 100 uint8_t value; 101 uint8_t device_index; 102 } persistent_ccc_entry_t; 103 104 // global 105 static btstack_packet_callback_registration_t hci_event_callback_registration; 106 static btstack_packet_callback_registration_t sm_event_callback_registration; 107 static btstack_packet_handler_t att_client_packet_handler; 108 static btstack_linked_list_t service_handlers; 109 static btstack_context_callback_registration_t att_client_waiting_for_can_send_registration; 110 111 static att_read_callback_t att_server_client_read_callback; 112 static att_write_callback_t att_server_client_write_callback; 113 114 // round robin 115 static hci_con_handle_t att_server_last_can_send_now = HCI_CON_HANDLE_INVALID; 116 117 static uint8_t att_server_flags; 118 119 #ifdef ENABLE_GATT_OVER_EATT 120 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle); 121 static btstack_linked_list_t att_server_eatt_bearer_pool; 122 static btstack_linked_list_t att_server_eatt_bearer_active; 123 #endif 124 125 #ifdef ENABLE_LE_SIGNED_WRITE 126 static bool att_server_connections_for_state(att_server_state_t state, att_server_t ** att_server_out, att_connection_t ** att_connection_out){ 127 btstack_linked_list_iterator_t it; 128 hci_connections_get_iterator(&it); 129 while(btstack_linked_list_iterator_has_next(&it)){ 130 hci_connection_t * hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 131 if (hci_connection->att_server.state == state) { 132 *att_server_out = &hci_connection->att_server; 133 *att_connection_out = &hci_connection->att_connection; 134 return true; 135 } 136 } 137 138 #ifdef ENABLE_GATT_OVER_EATT 139 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 140 while(btstack_linked_list_iterator_has_next(&it)){ 141 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 142 if (eatt_bearer->att_server.state == state) { 143 *att_server_out = &eatt_bearer->att_server; 144 *att_connection_out = &eatt_bearer->att_connection; 145 return true; 146 } 147 } 148 #endif 149 150 return false; 151 } 152 #endif 153 154 static void att_server_request_can_send_now(att_server_t * att_server, att_connection_t * att_connection ){ 155 switch (att_server->bearer_type){ 156 case ATT_BEARER_UNENHANCED_LE: 157 #ifdef ENABLE_GATT_OVER_CLASSIC 158 case ATT_BEARER_UNENHANCED_CLASSIC: 159 /* fall through */ 160 #endif 161 att_dispatch_server_request_can_send_now_event(att_connection->con_handle); 162 break; 163 #ifdef ENABLE_GATT_OVER_EATT 164 case ATT_BEARER_ENHANCED_LE: 165 l2cap_request_can_send_now_event(att_server->l2cap_cid); 166 break; 167 #endif 168 default: 169 btstack_unreachable(); 170 break; 171 } 172 } 173 174 static bool att_server_can_send_packet(att_server_t * att_server, att_connection_t * att_connection){ 175 switch (att_server->bearer_type) { 176 case ATT_BEARER_UNENHANCED_LE: 177 #ifdef ENABLE_GATT_OVER_CLASSIC 178 case ATT_BEARER_UNENHANCED_CLASSIC: 179 /* fall through */ 180 #endif 181 return att_dispatch_server_can_send_now(att_connection->con_handle); 182 #ifdef ENABLE_GATT_OVER_EATT 183 case ATT_BEARER_ENHANCED_LE: 184 return l2cap_can_send_packet_now(att_server->l2cap_cid); 185 #endif 186 default: 187 btstack_unreachable(); 188 break; 189 } 190 return false; 191 } 192 193 static void att_handle_value_indication_notify_client(uint8_t status, uint16_t client_handle, uint16_t attribute_handle){ 194 btstack_packet_handler_t packet_handler = att_server_packet_handler_for_handle(attribute_handle); 195 if (!packet_handler) return; 196 197 uint8_t event[7]; 198 int pos = 0; 199 event[pos++] = ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE; 200 event[pos++] = sizeof(event) - 2u; 201 event[pos++] = status; 202 little_endian_store_16(event, pos, client_handle); 203 pos += 2; 204 little_endian_store_16(event, pos, attribute_handle); 205 (*packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 206 } 207 208 static void att_emit_event_to_all(const uint8_t * event, uint16_t size){ 209 // dispatch to app level handler 210 if (att_client_packet_handler != NULL){ 211 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 212 } 213 214 // dispatch to service handlers 215 btstack_linked_list_iterator_t it; 216 btstack_linked_list_iterator_init(&it, &service_handlers); 217 while (btstack_linked_list_iterator_has_next(&it)){ 218 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 219 if (!handler->packet_handler) continue; 220 (*handler->packet_handler)(HCI_EVENT_PACKET, 0, (uint8_t*) event, size); 221 } 222 } 223 224 static void att_emit_mtu_event(hci_con_handle_t con_handle, uint16_t mtu){ 225 uint8_t event[6]; 226 int pos = 0; 227 event[pos++] = ATT_EVENT_MTU_EXCHANGE_COMPLETE; 228 event[pos++] = sizeof(event) - 2u; 229 little_endian_store_16(event, pos, con_handle); 230 pos += 2; 231 little_endian_store_16(event, pos, mtu); 232 233 // also dispatch to GATT Clients 234 att_dispatch_server_mtu_exchanged(con_handle, mtu); 235 236 // dispatch to app level handler and service handlers 237 att_emit_event_to_all(&event[0], sizeof(event)); 238 } 239 240 static void att_emit_can_send_now_event(void * context){ 241 UNUSED(context); 242 if (!att_client_packet_handler) return; 243 244 uint8_t event[] = { ATT_EVENT_CAN_SEND_NOW, 0}; 245 (*att_client_packet_handler)(HCI_EVENT_PACKET, 0, &event[0], sizeof(event)); 246 } 247 248 static void att_emit_connected_event(att_server_t * att_server, att_connection_t * att_connection){ 249 uint8_t event[11]; 250 int pos = 0; 251 event[pos++] = ATT_EVENT_CONNECTED; 252 event[pos++] = sizeof(event) - 2u; 253 event[pos++] = att_server->peer_addr_type; 254 reverse_bd_addr(att_server->peer_address, &event[pos]); 255 pos += 6; 256 little_endian_store_16(event, pos, att_connection->con_handle); 257 pos += 2; 258 259 // dispatch to app level handler and service handlers 260 att_emit_event_to_all(&event[0], sizeof(event)); 261 } 262 263 264 static void att_emit_disconnected_event(uint16_t con_handle){ 265 uint8_t event[4]; 266 int pos = 0; 267 event[pos++] = ATT_EVENT_DISCONNECTED; 268 event[pos++] = sizeof(event) - 2u; 269 little_endian_store_16(event, pos, con_handle); 270 pos += 2; 271 272 // dispatch to app level handler and service handlers 273 att_emit_event_to_all(&event[0], sizeof(event)); 274 } 275 276 static void att_handle_value_indication_timeout(btstack_timer_source_t *ts){ 277 void * context = btstack_run_loop_get_timer_context(ts); 278 hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context; 279 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 280 if (!hci_connection) return; 281 // @note: after a transaction timeout, no more requests shall be sent over this ATT Bearer 282 // (that's why we don't reset the value_indication_handle) 283 att_server_t * att_server = &hci_connection->att_server; 284 uint16_t att_handle = att_server->value_indication_handle; 285 att_connection_t * att_connection = &hci_connection->att_connection; 286 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_TIMEOUT, att_connection->con_handle, att_handle); 287 } 288 289 static void att_server_event_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 290 291 UNUSED(channel); // ok: there is no channel 292 UNUSED(size); // ok: handling own l2cap events 293 294 att_server_t * att_server; 295 att_connection_t * att_connection; 296 hci_con_handle_t con_handle; 297 hci_connection_t * hci_connection; 298 299 switch (packet_type) { 300 301 case HCI_EVENT_PACKET: 302 switch (hci_event_packet_get_type(packet)) { 303 case HCI_EVENT_META_GAP: 304 switch (hci_event_gap_meta_get_subevent_code(packet)) { 305 case GAP_SUBEVENT_LE_CONNECTION_COMPLETE: 306 con_handle = gap_subevent_le_connection_complete_get_connection_handle(packet); 307 hci_connection = hci_connection_for_handle(con_handle); 308 if (!hci_connection) break; 309 att_server = &hci_connection->att_server; 310 // store connection info 311 att_server->peer_addr_type = gap_subevent_le_connection_complete_get_peer_address_type(packet); 312 gap_subevent_le_connection_complete_get_peer_address(packet, att_server->peer_address); 313 att_connection = &hci_connection->att_connection; 314 att_connection->con_handle = con_handle; 315 // reset connection properties 316 att_server->state = ATT_SERVER_IDLE; 317 att_server->bearer_type = ATT_BEARER_UNENHANCED_LE; 318 att_connection->mtu = ATT_DEFAULT_MTU; 319 att_connection->max_mtu = l2cap_max_le_mtu(); 320 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 321 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 322 } 323 att_connection->encryption_key_size = 0u; 324 att_connection->authenticated = 0u; 325 att_connection->authorized = 0u; 326 // workaround: identity resolving can already be complete, at least store result 327 att_server->ir_le_device_db_index = sm_le_device_index(con_handle); 328 att_server->ir_lookup_active = false; 329 att_server->pairing_active = false; 330 // notify all - new 331 att_emit_connected_event(att_server, att_connection); 332 break; 333 default: 334 break; 335 } 336 break; 337 338 case HCI_EVENT_LE_META: 339 switch (hci_event_le_meta_get_subevent_code(packet)) { 340 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: 341 // forward LE Connection Complete event to keep backward compatibility 342 // deprecated: please register hci handler with hci_add_event_handler or handle ATT_EVENT_CONNECTED 343 att_emit_event_to_all(packet, size); 344 break; 345 default: 346 break; 347 } 348 break; 349 350 case HCI_EVENT_ENCRYPTION_CHANGE: 351 case HCI_EVENT_ENCRYPTION_CHANGE_V2: 352 case HCI_EVENT_ENCRYPTION_KEY_REFRESH_COMPLETE: 353 // check handle 354 con_handle = little_endian_read_16(packet, 3); 355 hci_connection = hci_connection_for_handle(con_handle); 356 if (!hci_connection) break; 357 if (gap_get_connection_type(con_handle) != GAP_CONNECTION_LE) break; 358 // update security params 359 att_server = &hci_connection->att_server; 360 att_connection = &hci_connection->att_connection; 361 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 362 att_connection->authenticated = gap_authenticated(con_handle) ? 1 : 0; 363 att_connection->secure_connection = gap_secure_connection(con_handle) ? 1 : 0; 364 log_info("encrypted key size %u, authenticated %u, secure connection %u", 365 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 366 if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE){ 367 // restore CCC values when encrypted for LE Connections 368 if (hci_event_encryption_change_get_encryption_enabled(packet) != 0){ 369 att_server_persistent_ccc_restore(att_server, att_connection); 370 } 371 } 372 att_run_for_context(att_server, att_connection); 373 break; 374 375 case HCI_EVENT_DISCONNECTION_COMPLETE: 376 // check handle 377 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 378 hci_connection = hci_connection_for_handle(con_handle); 379 if (!hci_connection) break; 380 att_server = &hci_connection->att_server; 381 att_connection = &hci_connection->att_connection; 382 att_clear_transaction_queue(att_connection); 383 att_connection->con_handle = 0; 384 att_server->pairing_active = false; 385 att_server->state = ATT_SERVER_IDLE; 386 if (att_server->value_indication_handle != 0u){ 387 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 388 uint16_t att_handle = att_server->value_indication_handle; 389 att_server->value_indication_handle = 0u; // reset error state 390 att_handle_value_indication_notify_client((uint8_t)ATT_HANDLE_VALUE_INDICATION_DISCONNECT, att_connection->con_handle, att_handle); 391 } 392 // notify all - new 393 att_emit_disconnected_event(con_handle); 394 // notify all - old 395 att_emit_event_to_all(packet, size); 396 break; 397 398 // Identity Resolving 399 case SM_EVENT_IDENTITY_RESOLVING_STARTED: 400 con_handle = sm_event_identity_resolving_started_get_handle(packet); 401 hci_connection = hci_connection_for_handle(con_handle); 402 if (!hci_connection) break; 403 att_server = &hci_connection->att_server; 404 log_info("SM_EVENT_IDENTITY_RESOLVING_STARTED"); 405 att_server->ir_lookup_active = true; 406 break; 407 case SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED: 408 con_handle = sm_event_identity_created_get_handle(packet); 409 hci_connection = hci_connection_for_handle(con_handle); 410 if (!hci_connection) return; 411 att_connection = &hci_connection->att_connection; 412 att_server = &hci_connection->att_server; 413 att_server->ir_lookup_active = false; 414 att_server->ir_le_device_db_index = sm_event_identity_resolving_succeeded_get_index(packet); 415 log_info("SM_EVENT_IDENTITY_RESOLVING_SUCCEEDED"); 416 att_run_for_context(att_server, att_connection); 417 break; 418 case SM_EVENT_IDENTITY_RESOLVING_FAILED: 419 con_handle = sm_event_identity_resolving_failed_get_handle(packet); 420 hci_connection = hci_connection_for_handle(con_handle); 421 if (!hci_connection) break; 422 att_connection = &hci_connection->att_connection; 423 att_server = &hci_connection->att_server; 424 log_info("SM_EVENT_IDENTITY_RESOLVING_FAILED"); 425 att_server->ir_lookup_active = false; 426 att_server->ir_le_device_db_index = -1; 427 att_run_for_context(att_server, att_connection); 428 break; 429 430 // Pairing started - delete stored CCC values 431 // - assumes pairing indicates either new device or re-pairing, in both cases there should be no stored CCC values 432 // - assumes that all events have the con handle as the first field 433 case SM_EVENT_JUST_WORKS_REQUEST: 434 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 435 case SM_EVENT_PASSKEY_INPUT_NUMBER: 436 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 437 con_handle = sm_event_just_works_request_get_handle(packet); 438 hci_connection = hci_connection_for_handle(con_handle); 439 if (!hci_connection) break; 440 att_server = &hci_connection->att_server; 441 log_info("SM Pairing started"); 442 att_server->pairing_active = true; 443 if (att_server->ir_le_device_db_index < 0) break; 444 att_server_persistent_ccc_clear(att_server); 445 // index not valid anymore 446 att_server->ir_le_device_db_index = -1; 447 break; 448 449 // Bonding completed 450 case SM_EVENT_IDENTITY_CREATED: 451 con_handle = sm_event_identity_created_get_handle(packet); 452 hci_connection = hci_connection_for_handle(con_handle); 453 if (!hci_connection) return; 454 att_connection = &hci_connection->att_connection; 455 att_server = &hci_connection->att_server; 456 att_server->pairing_active = false; 457 att_server->ir_le_device_db_index = sm_event_identity_created_get_index(packet); 458 att_run_for_context(att_server, att_connection); 459 break; 460 461 // Pairing complete (with/without bonding=storing of pairing information) 462 case SM_EVENT_PAIRING_COMPLETE: 463 con_handle = sm_event_pairing_complete_get_handle(packet); 464 hci_connection = hci_connection_for_handle(con_handle); 465 if (!hci_connection) return; 466 att_connection = &hci_connection->att_connection; 467 att_server = &hci_connection->att_server; 468 att_server->pairing_active = false; 469 att_run_for_context(att_server, att_connection); 470 break; 471 472 // Authorization 473 case SM_EVENT_AUTHORIZATION_RESULT: { 474 con_handle = sm_event_authorization_result_get_handle(packet); 475 hci_connection = hci_connection_for_handle(con_handle); 476 if (!hci_connection) break; 477 att_connection = &hci_connection->att_connection; 478 att_server = &hci_connection->att_server; 479 att_connection->authorized = sm_event_authorization_result_get_authorization_result(packet); 480 att_server_request_can_send_now(att_server, att_connection); 481 break; 482 } 483 default: 484 break; 485 } 486 break; 487 default: 488 break; 489 } 490 } 491 492 static uint8_t 493 att_server_send_prepared(const att_server_t *att_server, const att_connection_t *att_connection, uint8_t *buffer, 494 uint16_t size) { 495 UNUSED(buffer); 496 uint8_t status = ERROR_CODE_SUCCESS; 497 switch (att_server->bearer_type) { 498 case ATT_BEARER_UNENHANCED_LE: 499 status = l2cap_send_prepared_connectionless(att_connection->con_handle, L2CAP_CID_ATTRIBUTE_PROTOCOL, size); 500 break; 501 #ifdef ENABLE_GATT_OVER_CLASSIC 502 case ATT_BEARER_UNENHANCED_CLASSIC: 503 status = l2cap_send_prepared(att_server->l2cap_cid, size); 504 break; 505 #endif 506 #ifdef ENABLE_GATT_OVER_EATT 507 case ATT_BEARER_ENHANCED_LE: 508 btstack_assert(buffer != NULL); 509 status = l2cap_send(att_server->l2cap_cid, buffer, size); 510 break; 511 #endif 512 default: 513 btstack_unreachable(); 514 break; 515 } 516 return status; 517 } 518 519 #ifdef ENABLE_LE_SIGNED_WRITE 520 static void att_signed_write_handle_cmac_result(uint8_t hash[8]){ 521 att_server_t * att_server = NULL; 522 att_connection_t * att_connection = NULL; 523 bool found = att_server_connections_for_state(ATT_SERVER_W4_SIGNED_WRITE_VALIDATION, &att_server, &att_connection); 524 525 if (found == false){ 526 return; 527 } 528 529 uint8_t hash_flipped[8]; 530 reverse_64(hash, hash_flipped); 531 if (memcmp(hash_flipped, &att_server->request_buffer[att_server->request_size-8], 8) != 0){ 532 log_info("ATT Signed Write, invalid signature"); 533 #ifdef ENABLE_TESTING_SUPPORT 534 printf("ATT Signed Write, invalid signature\n"); 535 #endif 536 att_server->state = ATT_SERVER_IDLE; 537 return; 538 } 539 log_info("ATT Signed Write, valid signature"); 540 #ifdef ENABLE_TESTING_SUPPORT 541 printf("ATT Signed Write, valid signature\n"); 542 #endif 543 544 // update sequence number 545 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 546 le_device_db_remote_counter_set(att_server->ir_le_device_db_index, counter_packet+1); 547 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 548 att_server_request_can_send_now(att_server, att_connection); 549 } 550 #endif 551 552 #ifdef ENABLE_ATT_DELAYED_RESPONSE 553 static void att_server_handle_response_pending(att_server_t *att_server, const att_connection_t *att_connection, 554 const uint8_t *eatt_buffer, 555 uint16_t att_response_size) { 556 // update state 557 att_server->state = ATT_SERVER_RESPONSE_PENDING; 558 559 // callback with handle ATT_READ_RESPONSE_PENDING for reads 560 if (att_response_size == ATT_READ_RESPONSE_PENDING){ 561 // notify services that returned response pending 562 btstack_linked_list_iterator_t it; 563 btstack_linked_list_iterator_init(&it, &service_handlers); 564 while (btstack_linked_list_iterator_has_next(&it)) { 565 att_service_handler_t *handler = (att_service_handler_t *) btstack_linked_list_iterator_next(&it); 566 if ((handler->flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 567 handler->flags &= ~ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 568 handler->read_callback(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 569 } 570 } 571 // notify main read callback if it returned response pending 572 if ((att_server_flags & ATT_SERVICE_FLAGS_DELAYED_RESPONSE) != 0){ 573 // flag was set by read callback 574 btstack_assert(att_server_client_read_callback != NULL); 575 (*att_server_client_read_callback)(att_connection->con_handle, ATT_READ_RESPONSE_PENDING, 0, NULL, 0); 576 } 577 } 578 579 // free reserved buffer - might trigger next read/write 580 if (eatt_buffer == NULL){ 581 l2cap_release_packet_buffer(); 582 } 583 } 584 #endif 585 586 // pre: att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED 587 // pre: can send now 588 // uses l2cap outgoing buffer if no eatt_buffer provided 589 // returns: 1 if packet was sent 590 static int 591 att_server_process_validated_request(att_server_t *att_server, att_connection_t *att_connection, uint8_t *eatt_buffer) { 592 593 uint8_t * att_response_buffer; 594 if (eatt_buffer != NULL){ 595 att_response_buffer = eatt_buffer; 596 } else { 597 l2cap_reserve_packet_buffer(); 598 att_response_buffer = l2cap_get_outgoing_buffer(); 599 } 600 601 uint16_t att_response_size = 0; 602 // Send Error Response for MTU Request over connection-oriented channel 603 if ((att_server->bearer_type != ATT_BEARER_UNENHANCED_LE) && (att_server->request_buffer[0] == ATT_EXCHANGE_MTU_REQUEST)){ 604 att_response_size = 5; 605 att_response_buffer[0] = ATT_ERROR_RESPONSE; 606 att_response_buffer[1] = ATT_EXCHANGE_MTU_REQUEST; 607 att_response_buffer[2] = 0; 608 att_response_buffer[3] = 0; 609 att_response_buffer[4] = ATT_ERROR_REQUEST_NOT_SUPPORTED; 610 } else { 611 att_response_size = att_handle_request(att_connection, att_server->request_buffer, att_server->request_size, att_response_buffer); 612 } 613 614 #ifdef ENABLE_ATT_DELAYED_RESPONSE 615 if ((att_response_size == ATT_READ_RESPONSE_PENDING) || (att_response_size == ATT_INTERNAL_WRITE_RESPONSE_PENDING)){ 616 att_server_handle_response_pending(att_server, att_connection, eatt_buffer, att_response_size); 617 return 0; 618 } 619 #endif 620 621 // intercept "insufficient authorization" for authenticated connections to allow for user authorization 622 if ((att_response_size >= 4u) 623 && (att_response_buffer[0] == ATT_ERROR_RESPONSE) 624 && (att_response_buffer[4] == ATT_ERROR_INSUFFICIENT_AUTHORIZATION) 625 && (att_connection->authenticated != 0u)){ 626 627 switch (gap_authorization_state(att_connection->con_handle)){ 628 case AUTHORIZATION_UNKNOWN: 629 if (eatt_buffer == NULL){ 630 l2cap_release_packet_buffer(); 631 } 632 sm_request_pairing(att_connection->con_handle); 633 return 0; 634 case AUTHORIZATION_PENDING: 635 if (eatt_buffer == NULL){ 636 l2cap_release_packet_buffer(); 637 } 638 return 0; 639 default: 640 break; 641 } 642 } 643 644 att_server->state = ATT_SERVER_IDLE; 645 if (att_response_size == 0u) { 646 if (eatt_buffer == NULL){ 647 l2cap_release_packet_buffer(); 648 } 649 return 0; 650 } 651 652 (void) att_server_send_prepared(att_server, att_connection, eatt_buffer, att_response_size); 653 654 // notify client about MTU exchange result 655 if (att_response_buffer[0] == ATT_EXCHANGE_MTU_RESPONSE){ 656 att_emit_mtu_event(att_connection->con_handle, att_connection->mtu); 657 } 658 return 1; 659 } 660 661 #ifdef ENABLE_ATT_DELAYED_RESPONSE 662 uint8_t att_server_response_ready(hci_con_handle_t con_handle){ 663 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 664 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 665 att_server_t * att_server = &hci_connection->att_server; 666 att_connection_t * att_connection = &hci_connection->att_connection; 667 if (att_server->state != ATT_SERVER_RESPONSE_PENDING) return ERROR_CODE_COMMAND_DISALLOWED; 668 669 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 670 att_server_request_can_send_now(att_server, att_connection); 671 return ERROR_CODE_SUCCESS; 672 } 673 #endif 674 675 static void att_run_for_context(att_server_t * att_server, att_connection_t * att_connection){ 676 switch (att_server->state){ 677 case ATT_SERVER_REQUEST_RECEIVED: 678 switch (att_server->bearer_type){ 679 case ATT_BEARER_UNENHANCED_LE: 680 // wait until re-encryption as central is complete 681 if (gap_reconnect_security_setup_active(att_connection->con_handle)) { 682 return; 683 }; 684 break; 685 #if defined(ENABLE_GATT_OVER_CLASSIC) || defined (ENABLE_GATT_OVER_EATT) 686 #ifdef ENABLE_GATT_OVER_CLASSIC 687 case ATT_BEARER_UNENHANCED_CLASSIC: 688 /* fall through */ 689 #endif 690 #ifdef ENABLE_GATT_OVER_EATT 691 case ATT_BEARER_ENHANCED_LE: 692 #endif 693 // ok 694 break; 695 #endif 696 default: 697 btstack_unreachable(); 698 break; 699 } 700 701 // wait until pairing is complete 702 if (att_server->pairing_active) break; 703 704 #ifdef ENABLE_LE_SIGNED_WRITE 705 if (att_server->request_buffer[0] == ATT_SIGNED_WRITE_COMMAND){ 706 log_info("ATT Signed Write!"); 707 if (!sm_cmac_ready()) { 708 log_info("ATT Signed Write, sm_cmac engine not ready. Abort"); 709 att_server->state = ATT_SERVER_IDLE; 710 return; 711 } 712 if (att_server->request_size < (3 + 12)) { 713 log_info("ATT Signed Write, request to short. Abort."); 714 att_server->state = ATT_SERVER_IDLE; 715 return; 716 } 717 if (att_server->ir_lookup_active){ 718 return; 719 } 720 if (att_server->ir_le_device_db_index < 0){ 721 log_info("ATT Signed Write, CSRK not available"); 722 att_server->state = ATT_SERVER_IDLE; 723 return; 724 } 725 726 // check counter 727 uint32_t counter_packet = little_endian_read_32(att_server->request_buffer, att_server->request_size-12); 728 uint32_t counter_db = le_device_db_remote_counter_get(att_server->ir_le_device_db_index); 729 log_info("ATT Signed Write, DB counter %"PRIu32", packet counter %"PRIu32, counter_db, counter_packet); 730 if (counter_packet < counter_db){ 731 log_info("ATT Signed Write, db reports higher counter, abort"); 732 att_server->state = ATT_SERVER_IDLE; 733 return; 734 } 735 736 // signature is { sequence counter, secure hash } 737 sm_key_t csrk; 738 le_device_db_remote_csrk_get(att_server->ir_le_device_db_index, csrk); 739 att_server->state = ATT_SERVER_W4_SIGNED_WRITE_VALIDATION; 740 log_info("Orig Signature: "); 741 log_info_hexdump( &att_server->request_buffer[att_server->request_size-8], 8); 742 uint16_t attribute_handle = little_endian_read_16(att_server->request_buffer, 1); 743 sm_cmac_signed_write_start(csrk, att_server->request_buffer[0], attribute_handle, att_server->request_size - 15, &att_server->request_buffer[3], counter_packet, att_signed_write_handle_cmac_result); 744 return; 745 } 746 #endif 747 // move on 748 att_server->state = ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 749 att_server_request_can_send_now(att_server, att_connection); 750 break; 751 752 default: 753 break; 754 } 755 } 756 757 static bool att_server_data_ready_for_phase(att_server_t * att_server, att_server_run_phase_t phase){ 758 switch (phase){ 759 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 760 return att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED; 761 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 762 return (!btstack_linked_list_empty(&att_server->indication_requests) && (att_server->value_indication_handle == 0u)); 763 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 764 return (!btstack_linked_list_empty(&att_server->notification_requests)); 765 default: 766 btstack_assert(false); 767 return false; 768 } 769 } 770 771 static void att_server_trigger_send_for_phase(att_server_t * att_server, att_connection_t * att_connection, att_server_run_phase_t phase){ 772 btstack_context_callback_registration_t * client; 773 switch (phase){ 774 case ATT_SERVER_RUN_PHASE_1_REQUESTS: 775 att_server_process_validated_request(att_server, att_connection, NULL); 776 break; 777 case ATT_SERVER_RUN_PHASE_2_INDICATIONS: 778 client = (btstack_context_callback_registration_t*) att_server->indication_requests; 779 btstack_linked_list_remove(&att_server->indication_requests, (btstack_linked_item_t *) client); 780 client->callback(client->context); 781 break; 782 case ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS: 783 client = (btstack_context_callback_registration_t*) att_server->notification_requests; 784 btstack_linked_list_remove(&att_server->notification_requests, (btstack_linked_item_t *) client); 785 client->callback(client->context); 786 break; 787 default: 788 btstack_assert(false); 789 break; 790 } 791 } 792 793 static void att_server_handle_can_send_now(void){ 794 795 hci_con_handle_t last_send_con_handle = HCI_CON_HANDLE_INVALID; 796 hci_connection_t * request_hci_connection = NULL; 797 bool can_send_now = true; 798 uint8_t phase_index; 799 800 for (phase_index = ATT_SERVER_RUN_PHASE_1_REQUESTS; phase_index <= ATT_SERVER_RUN_PHASE_3_NOTIFICATIONS; phase_index++){ 801 att_server_run_phase_t phase = (att_server_run_phase_t) phase_index; 802 hci_con_handle_t skip_connections_until = att_server_last_can_send_now; 803 while (true){ 804 btstack_linked_list_iterator_t it; 805 hci_connections_get_iterator(&it); 806 while(btstack_linked_list_iterator_has_next(&it)){ 807 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 808 att_server_t * att_server = &connection->att_server; 809 att_connection_t * att_connection = &connection->att_connection; 810 811 bool data_ready = att_server_data_ready_for_phase(att_server, phase); 812 813 // log_debug("phase %u, handle 0x%04x, skip until 0x%04x, data ready %u", phase, att_connection->con_handle, skip_connections_until, data_ready); 814 815 // skip until last sender found (which is also skipped) 816 if (skip_connections_until != HCI_CON_HANDLE_INVALID){ 817 if (data_ready && (request_hci_connection == NULL)){ 818 request_hci_connection = connection; 819 } 820 if (skip_connections_until == att_connection->con_handle){ 821 skip_connections_until = HCI_CON_HANDLE_INVALID; 822 } 823 continue; 824 }; 825 826 if (data_ready){ 827 if (can_send_now){ 828 att_server_trigger_send_for_phase(att_server, att_connection, phase); 829 last_send_con_handle = att_connection->con_handle; 830 can_send_now = att_server_can_send_packet(att_server, att_connection); 831 data_ready = att_server_data_ready_for_phase(att_server, phase); 832 if (data_ready && (request_hci_connection == NULL)){ 833 request_hci_connection = connection; 834 } 835 } else { 836 request_hci_connection = connection; 837 break; 838 } 839 } 840 } 841 842 // stop skipping (handles disconnect by last send connection) 843 skip_connections_until = HCI_CON_HANDLE_INVALID; 844 845 // Exit loop, if we cannot send 846 if (!can_send_now) break; 847 848 // Exit loop, if we can send but there are also no further request 849 if (request_hci_connection == NULL) break; 850 851 // Finally, if we still can send and there are requests, just try again 852 request_hci_connection = NULL; 853 } 854 // update last send con handle for round robin 855 if (last_send_con_handle != HCI_CON_HANDLE_INVALID){ 856 att_server_last_can_send_now = last_send_con_handle; 857 } 858 } 859 860 if (request_hci_connection == NULL) return; 861 862 att_server_t * att_server = &request_hci_connection->att_server; 863 att_connection_t * att_connection = &request_hci_connection->att_connection; 864 att_server_request_can_send_now(att_server, att_connection); 865 } 866 867 static void att_server_handle_att_pdu(att_server_t * att_server, att_connection_t * att_connection, uint8_t * packet, uint16_t size){ 868 869 uint8_t opcode = packet[0u]; 870 uint8_t method = opcode & 0x03fu; 871 bool invalid = method > ATT_MULTIPLE_HANDLE_VALUE_NTF; 872 bool command = (opcode & 0x40u) != 0u; 873 874 // ignore invalid commands 875 if (invalid && command){ 876 return; 877 } 878 879 // handle value indication confirms 880 if ((opcode == ATT_HANDLE_VALUE_CONFIRMATION) && (att_server->value_indication_handle != 0u)){ 881 btstack_run_loop_remove_timer(&att_server->value_indication_timer); 882 uint16_t att_handle = att_server->value_indication_handle; 883 att_server->value_indication_handle = 0u; 884 att_handle_value_indication_notify_client(0u, att_connection->con_handle, att_handle); 885 att_server_request_can_send_now(att_server, att_connection); 886 return; 887 } 888 889 // directly process command 890 // note: signed write cannot be handled directly as authentication needs to be verified 891 if (opcode == ATT_WRITE_COMMAND){ 892 att_handle_request(att_connection, packet, size, NULL); 893 return; 894 } 895 896 // check size 897 if (size > sizeof(att_server->request_buffer)) { 898 log_info("drop att pdu 0x%02x as size %u > att_server->request_buffer %u", packet[0], size, (int) sizeof(att_server->request_buffer)); 899 return; 900 } 901 902 #ifdef ENABLE_LE_SIGNED_WRITE 903 // abort signed write validation if a new request comes in (but finish previous signed write if possible) 904 if (att_server->state == ATT_SERVER_W4_SIGNED_WRITE_VALIDATION){ 905 if (packet[0] == ATT_SIGNED_WRITE_COMMAND){ 906 log_info("skip new signed write request as previous is in validation"); 907 return; 908 } else { 909 log_info("abort signed write validation to process new request"); 910 att_server->state = ATT_SERVER_IDLE; 911 } 912 } 913 #endif 914 // last request still in processing? 915 if (att_server->state != ATT_SERVER_IDLE){ 916 log_info("skip att pdu 0x%02x as server not idle (state %u)", packet[0], att_server->state); 917 return; 918 } 919 920 // store request 921 att_server->state = ATT_SERVER_REQUEST_RECEIVED; 922 att_server->request_size = size; 923 (void)memcpy(att_server->request_buffer, packet, size); 924 925 att_run_for_context(att_server, att_connection); 926 } 927 928 static void att_server_dispatch_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 929 hci_connection_t * hci_connection; 930 att_connection_t * att_connection; 931 att_server_t * att_server; 932 #ifdef ENABLE_GATT_OVER_CLASSIC 933 hci_con_handle_t con_handle; 934 bd_addr_t address; 935 btstack_linked_list_iterator_t it; 936 #endif 937 938 switch (packet_type){ 939 case HCI_EVENT_PACKET: 940 switch (packet[0]){ 941 #ifdef ENABLE_GATT_OVER_CLASSIC 942 case L2CAP_EVENT_CHANNEL_OPENED: 943 con_handle = l2cap_event_channel_opened_get_handle(packet); 944 hci_connection = hci_connection_for_handle(con_handle); 945 if (!hci_connection) break; 946 att_server = &hci_connection->att_server; 947 // store connection info 948 att_server->bearer_type = ATT_BEARER_UNENHANCED_CLASSIC; 949 att_server->peer_addr_type = BD_ADDR_TYPE_ACL; 950 l2cap_event_channel_opened_get_address(packet, att_server->peer_address); 951 att_connection = &hci_connection->att_connection; 952 att_connection->con_handle = con_handle; 953 // reset connection properties 954 att_server->state = ATT_SERVER_IDLE; 955 att_connection->mtu = l2cap_event_channel_opened_get_remote_mtu(packet); 956 att_connection->max_mtu = l2cap_max_mtu(); 957 if (att_connection->max_mtu > ATT_REQUEST_BUFFER_SIZE){ 958 att_connection->max_mtu = ATT_REQUEST_BUFFER_SIZE; 959 } 960 961 log_info("Connection opened %s, l2cap cid %04x, mtu %u", bd_addr_to_str(address), att_server->l2cap_cid, att_connection->mtu); 962 963 // update security params 964 att_connection->encryption_key_size = gap_encryption_key_size(con_handle); 965 att_connection->authenticated = gap_authenticated(con_handle); 966 att_connection->secure_connection = gap_secure_connection(con_handle); 967 log_info("encrypted key size %u, authenticated %u, secure connection %u", 968 att_connection->encryption_key_size, att_connection->authenticated, att_connection->secure_connection); 969 970 // notify connection opened 971 att_emit_connected_event(att_server, att_connection); 972 973 // restore persisten ccc if encrypted 974 if ( gap_security_level(con_handle) >= LEVEL_2){ 975 att_server_persistent_ccc_restore(att_server, att_connection); 976 } 977 // TODO: what to do about le device db? 978 att_server->pairing_active = 0; 979 break; 980 #endif 981 case L2CAP_EVENT_CAN_SEND_NOW: 982 att_server_handle_can_send_now(); 983 break; 984 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 985 // GATT client has negotiated the mtu for this connection 986 hci_connection = hci_connection_for_handle(channel); 987 if (!hci_connection) break; 988 att_connection = &hci_connection->att_connection; 989 att_connection->mtu = little_endian_read_16(packet, 4); 990 break; 991 default: 992 break; 993 } 994 break; 995 996 case ATT_DATA_PACKET: 997 log_debug("ATT Packet, handle 0x%04x", channel); 998 hci_connection = hci_connection_for_handle(channel); 999 if (!hci_connection) break; 1000 1001 att_server = &hci_connection->att_server; 1002 att_connection = &hci_connection->att_connection; 1003 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1004 break; 1005 1006 #ifdef ENABLE_GATT_OVER_CLASSIC 1007 case L2CAP_DATA_PACKET: 1008 hci_connections_get_iterator(&it); 1009 while(btstack_linked_list_iterator_has_next(&it)){ 1010 hci_connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 1011 att_server = &hci_connection->att_server; 1012 att_connection = &hci_connection->att_connection; 1013 if (att_server->l2cap_cid == channel) { 1014 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1015 break; 1016 } 1017 } 1018 break; 1019 #endif 1020 1021 default: 1022 break; 1023 } 1024 } 1025 1026 // --------------------- 1027 // persistent CCC writes 1028 static uint32_t att_server_persistent_ccc_tag_for_index(uint8_t index){ 1029 return ('B' << 24u) | ('T' << 16u) | ('C' << 8u) | index; 1030 } 1031 1032 static void att_server_persistent_ccc_write(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t value){ 1033 // lookup att_server instance 1034 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1035 if (!hci_connection) return; 1036 att_server_t * att_server = &hci_connection->att_server; 1037 int le_device_index = att_server->ir_le_device_db_index; 1038 log_info("Store CCC value 0x%04x for handle 0x%04x of remote %s, le device id %d", value, att_handle, bd_addr_to_str(att_server->peer_address), le_device_index); 1039 1040 // check if bonded 1041 if (le_device_index < 0) return; 1042 1043 // get btstack_tlv 1044 const btstack_tlv_t * tlv_impl = NULL; 1045 void * tlv_context; 1046 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1047 if (!tlv_impl) return; 1048 1049 // update ccc tag 1050 int index; 1051 uint32_t highest_seq_nr = 0; 1052 uint32_t lowest_seq_nr = 0; 1053 uint32_t tag_for_lowest_seq_nr = 0; 1054 uint32_t tag_for_empty = 0; 1055 persistent_ccc_entry_t entry; 1056 for (index=0; index<NVN_NUM_GATT_SERVER_CCC; index++){ 1057 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1058 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1059 1060 // empty/invalid tag 1061 if (len != sizeof(persistent_ccc_entry_t)){ 1062 tag_for_empty = tag; 1063 continue; 1064 } 1065 // update highest seq nr 1066 if (entry.seq_nr > highest_seq_nr){ 1067 highest_seq_nr = entry.seq_nr; 1068 } 1069 // find entry with lowest seq nr 1070 if ((tag_for_lowest_seq_nr == 0u) || (entry.seq_nr < lowest_seq_nr)){ 1071 tag_for_lowest_seq_nr = tag; 1072 lowest_seq_nr = entry.seq_nr; 1073 } 1074 1075 if (entry.device_index != le_device_index) continue; 1076 if (entry.att_handle != att_handle) continue; 1077 1078 // found matching entry 1079 if (value != 0){ 1080 // update 1081 if (entry.value == value) { 1082 log_info("CCC Index %u: Up-to-date", index); 1083 return; 1084 } 1085 entry.value = (uint8_t) value; 1086 entry.seq_nr = highest_seq_nr + 1u; 1087 log_info("CCC Index %u: Store", index); 1088 int result = tlv_impl->store_tag(tlv_context, tag, (const uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1089 if (result != 0){ 1090 log_error("Store tag index %u failed", index); 1091 } 1092 } else { 1093 // delete 1094 log_info("CCC Index %u: Delete", index); 1095 tlv_impl->delete_tag(tlv_context, tag); 1096 } 1097 return; 1098 } 1099 1100 log_info("tag_for_empty %"PRIx32", tag_for_lowest_seq_nr %"PRIx32, tag_for_empty, tag_for_lowest_seq_nr); 1101 1102 if (value == 0u){ 1103 // done 1104 return; 1105 } 1106 1107 uint32_t tag_to_use = 0u; 1108 if (tag_for_empty != 0u){ 1109 tag_to_use = tag_for_empty; 1110 } else if (tag_for_lowest_seq_nr != 0){ 1111 tag_to_use = tag_for_lowest_seq_nr; 1112 } else { 1113 // should not happen 1114 return; 1115 } 1116 // store ccc tag 1117 entry.seq_nr = highest_seq_nr + 1u; 1118 entry.device_index = le_device_index; 1119 entry.att_handle = att_handle; 1120 entry.value = (uint8_t) value; 1121 int result = tlv_impl->store_tag(tlv_context, tag_to_use, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1122 if (result != 0){ 1123 log_error("Store tag index %u failed", index); 1124 } 1125 } 1126 1127 static void att_server_persistent_ccc_clear(att_server_t * att_server){ 1128 int le_device_index = att_server->ir_le_device_db_index; 1129 log_info("Clear CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1130 // check if bonded 1131 if (le_device_index < 0) return; 1132 // get btstack_tlv 1133 const btstack_tlv_t * tlv_impl = NULL; 1134 void * tlv_context; 1135 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1136 if (!tlv_impl) return; 1137 // get all ccc tag 1138 int index; 1139 persistent_ccc_entry_t entry; 1140 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1141 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1142 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1143 if (len != sizeof(persistent_ccc_entry_t)) continue; 1144 if (entry.device_index != le_device_index) continue; 1145 // delete entry 1146 log_info("CCC Index %u: Delete", index); 1147 tlv_impl->delete_tag(tlv_context, tag); 1148 } 1149 } 1150 1151 static void att_server_persistent_ccc_restore(att_server_t * att_server, att_connection_t * att_connection){ 1152 int le_device_index = att_server->ir_le_device_db_index; 1153 log_info("Restore CCC values of remote %s, le device id %d", bd_addr_to_str(att_server->peer_address), le_device_index); 1154 // check if bonded 1155 if (le_device_index < 0) return; 1156 // get btstack_tlv 1157 const btstack_tlv_t * tlv_impl = NULL; 1158 void * tlv_context; 1159 btstack_tlv_get_instance(&tlv_impl, &tlv_context); 1160 if (!tlv_impl) return; 1161 // get all ccc tag 1162 int index; 1163 persistent_ccc_entry_t entry; 1164 for (index=0;index<NVN_NUM_GATT_SERVER_CCC;index++){ 1165 uint32_t tag = att_server_persistent_ccc_tag_for_index(index); 1166 int len = tlv_impl->get_tag(tlv_context, tag, (uint8_t *) &entry, sizeof(persistent_ccc_entry_t)); 1167 if (len != sizeof(persistent_ccc_entry_t)) continue; 1168 if (entry.device_index != le_device_index) continue; 1169 // simulate write callback 1170 uint16_t attribute_handle = entry.att_handle; 1171 uint8_t value[2]; 1172 little_endian_store_16(value, 0, entry.value); 1173 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1174 if (!callback) continue; 1175 log_info("CCC Index %u: Set Attribute handle 0x%04x to value 0x%04x", index, attribute_handle, entry.value ); 1176 (*callback)(att_connection->con_handle, attribute_handle, ATT_TRANSACTION_MODE_NONE, 0, value, sizeof(value)); 1177 } 1178 } 1179 1180 // persistent CCC writes 1181 // --------------------- 1182 1183 // gatt service management 1184 static att_service_handler_t * att_service_handler_for_handle(uint16_t handle){ 1185 btstack_linked_list_iterator_t it; 1186 btstack_linked_list_iterator_init(&it, &service_handlers); 1187 while (btstack_linked_list_iterator_has_next(&it)){ 1188 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1189 if (handler->start_handle > handle) continue; 1190 if (handler->end_handle < handle) continue; 1191 return handler; 1192 } 1193 return NULL; 1194 } 1195 1196 static att_write_callback_t att_server_write_callback_for_handle(uint16_t handle){ 1197 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1198 if (handler != NULL) return handler->write_callback; 1199 return att_server_client_write_callback; 1200 } 1201 1202 static btstack_packet_handler_t att_server_packet_handler_for_handle(uint16_t handle){ 1203 att_service_handler_t * handler = att_service_handler_for_handle(handle); 1204 if (handler != NULL) return handler->packet_handler; 1205 return att_client_packet_handler; 1206 } 1207 1208 static void att_notify_write_callbacks(hci_con_handle_t con_handle, uint16_t transaction_mode){ 1209 // notify all callbacks 1210 btstack_linked_list_iterator_t it; 1211 btstack_linked_list_iterator_init(&it, &service_handlers); 1212 while (btstack_linked_list_iterator_has_next(&it)){ 1213 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1214 if (!handler->write_callback) continue; 1215 (*handler->write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1216 } 1217 if (!att_server_client_write_callback) return; 1218 (*att_server_client_write_callback)(con_handle, 0, transaction_mode, 0, NULL, 0); 1219 } 1220 1221 // returns first reported error or 0 1222 static uint8_t att_validate_prepared_write(hci_con_handle_t con_handle){ 1223 btstack_linked_list_iterator_t it; 1224 btstack_linked_list_iterator_init(&it, &service_handlers); 1225 while (btstack_linked_list_iterator_has_next(&it)){ 1226 att_service_handler_t * handler = (att_service_handler_t*) btstack_linked_list_iterator_next(&it); 1227 if (!handler->write_callback) continue; 1228 uint8_t error_code = (*handler->write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1229 if (error_code != 0u) return error_code; 1230 } 1231 if (!att_server_client_write_callback) return 0; 1232 return (*att_server_client_write_callback)(con_handle, 0, ATT_TRANSACTION_MODE_VALIDATE, 0, NULL, 0); 1233 } 1234 1235 static uint16_t att_server_read_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 1236 att_service_handler_t * service = att_service_handler_for_handle(attribute_handle); 1237 att_read_callback_t read_callback = (service != NULL) ? service->read_callback : att_server_client_read_callback; 1238 uint16_t result = 0; 1239 if (read_callback != NULL){ 1240 result = (*read_callback)(con_handle, attribute_handle, offset, buffer, buffer_size); 1241 #ifdef ENABLE_ATT_DELAYED_RESPONSE 1242 if (result == ATT_READ_RESPONSE_PENDING){ 1243 if (service == NULL){ 1244 att_server_flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1245 } else { 1246 service->flags |= ATT_SERVICE_FLAGS_DELAYED_RESPONSE; 1247 } 1248 } 1249 #endif 1250 } 1251 return result; 1252 } 1253 1254 static int att_server_write_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size){ 1255 switch (transaction_mode){ 1256 case ATT_TRANSACTION_MODE_VALIDATE: 1257 return att_validate_prepared_write(con_handle); 1258 case ATT_TRANSACTION_MODE_EXECUTE: 1259 case ATT_TRANSACTION_MODE_CANCEL: 1260 att_notify_write_callbacks(con_handle, transaction_mode); 1261 return 0; 1262 default: 1263 break; 1264 } 1265 1266 // track CCC writes 1267 if (att_is_persistent_ccc(attribute_handle) && (offset == 0u) && (buffer_size == 2u)){ 1268 att_server_persistent_ccc_write(con_handle, attribute_handle, little_endian_read_16(buffer, 0)); 1269 } 1270 1271 att_write_callback_t callback = att_server_write_callback_for_handle(attribute_handle); 1272 if (!callback) return 0; 1273 return (*callback)(con_handle, attribute_handle, transaction_mode, offset, buffer, buffer_size); 1274 } 1275 1276 /** 1277 * @brief register read/write callbacks for specific handle range 1278 * @param att_service_handler_t 1279 */ 1280 void att_server_register_service_handler(att_service_handler_t * handler){ 1281 bool att_server_registered = false; 1282 if (att_service_handler_for_handle(handler->start_handle) != NULL){ 1283 att_server_registered = true; 1284 } 1285 1286 if (att_service_handler_for_handle(handler->end_handle) != NULL){ 1287 att_server_registered = true; 1288 } 1289 1290 if (att_server_registered){ 1291 log_error("handler for range 0x%04x-0x%04x already registered", handler->start_handle, handler->end_handle); 1292 return; 1293 } 1294 1295 handler->flags = 0; 1296 btstack_linked_list_add(&service_handlers, (btstack_linked_item_t*) handler); 1297 } 1298 1299 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback){ 1300 1301 // store callbacks 1302 att_server_client_read_callback = read_callback; 1303 att_server_client_write_callback = write_callback; 1304 1305 // register for HCI Events 1306 hci_event_callback_registration.callback = &att_server_event_packet_handler; 1307 hci_add_event_handler(&hci_event_callback_registration); 1308 1309 // register for SM events 1310 sm_event_callback_registration.callback = &att_server_event_packet_handler; 1311 sm_add_event_handler(&sm_event_callback_registration); 1312 1313 // and L2CAP ATT Server PDUs 1314 att_dispatch_register_server(att_server_dispatch_packet_handler); 1315 1316 #ifdef ENABLE_GATT_OVER_CLASSIC 1317 // setup l2cap service 1318 att_dispatch_classic_register_service(); 1319 #endif 1320 1321 att_set_db(db); 1322 att_set_read_callback(att_server_read_callback); 1323 att_set_write_callback(att_server_write_callback); 1324 } 1325 1326 void att_server_register_packet_handler(btstack_packet_handler_t handler){ 1327 att_client_packet_handler = handler; 1328 } 1329 1330 1331 // to be deprecated 1332 int att_server_can_send_packet_now(hci_con_handle_t con_handle){ 1333 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1334 if (!hci_connection) return 0; 1335 att_server_t * att_server = &hci_connection->att_server; 1336 att_connection_t * att_connection = &hci_connection->att_connection; 1337 return att_server_can_send_packet(att_server, att_connection); 1338 } 1339 1340 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1341 return att_server_request_to_send_notification(callback_registration, con_handle); 1342 } 1343 1344 void att_server_request_can_send_now_event(hci_con_handle_t con_handle){ 1345 att_client_waiting_for_can_send_registration.callback = &att_emit_can_send_now_event; 1346 att_server_request_to_send_notification(&att_client_waiting_for_can_send_registration, con_handle); 1347 } 1348 // end of deprecated 1349 1350 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1351 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1352 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1353 att_server_t * att_server = &hci_connection->att_server; 1354 att_connection_t * att_connection = &hci_connection->att_connection; 1355 bool added = btstack_linked_list_add_tail(&att_server->notification_requests, (btstack_linked_item_t*) callback_registration); 1356 att_server_request_can_send_now(att_server, att_connection); 1357 if (added){ 1358 return ERROR_CODE_SUCCESS; 1359 } else { 1360 return ERROR_CODE_COMMAND_DISALLOWED; 1361 } 1362 } 1363 1364 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle){ 1365 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1366 if (!hci_connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1367 att_server_t * att_server = &hci_connection->att_server; 1368 att_connection_t * att_connection = &hci_connection->att_connection; 1369 bool added = btstack_linked_list_add_tail(&att_server->indication_requests, (btstack_linked_item_t*) callback_registration); 1370 att_server_request_can_send_now(att_server, att_connection); 1371 if (added){ 1372 return ERROR_CODE_SUCCESS; 1373 } else { 1374 return ERROR_CODE_COMMAND_DISALLOWED; 1375 } 1376 } 1377 1378 static uint8_t att_server_prepare_server_message(hci_con_handle_t con_handle, att_server_t ** out_att_server, att_connection_t ** out_att_connection, uint8_t ** out_packet_buffer){ 1379 1380 att_server_t * att_server = NULL; 1381 att_connection_t * att_connection = NULL; 1382 uint8_t * packet_buffer = NULL; 1383 1384 // prefer enhanced bearer 1385 #ifdef ENABLE_GATT_OVER_EATT 1386 att_server_eatt_bearer_t * eatt_bearer = att_server_eatt_bearer_for_con_handle(con_handle); 1387 if (eatt_bearer != NULL){ 1388 att_server = &eatt_bearer->att_server; 1389 att_connection = &eatt_bearer->att_connection; 1390 packet_buffer = eatt_bearer->send_buffer; 1391 } else 1392 #endif 1393 { 1394 hci_connection_t *hci_connection = hci_connection_for_handle(con_handle); 1395 if (hci_connection != NULL) { 1396 att_server = &hci_connection->att_server; 1397 att_connection = &hci_connection->att_connection; 1398 } 1399 } 1400 1401 if (att_server == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1402 if (!att_server_can_send_packet(att_server, att_connection)) return BTSTACK_ACL_BUFFERS_FULL; 1403 1404 if (packet_buffer == NULL){ 1405 l2cap_reserve_packet_buffer(); 1406 packet_buffer = l2cap_get_outgoing_buffer(); 1407 } 1408 1409 *out_att_connection = att_connection; 1410 *out_att_server = att_server; 1411 *out_packet_buffer = packet_buffer; 1412 return ERROR_CODE_SUCCESS; 1413 } 1414 1415 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1416 att_server_t * att_server = NULL; 1417 att_connection_t * att_connection = NULL; 1418 uint8_t * packet_buffer = NULL; 1419 1420 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1421 if (status != ERROR_CODE_SUCCESS){ 1422 return status; 1423 } 1424 1425 uint16_t size = att_prepare_handle_value_notification(att_connection, attribute_handle, value, value_len, packet_buffer); 1426 1427 return att_server_send_prepared(att_server, att_connection, NULL, size); 1428 } 1429 1430 /** 1431 * @brief notify client about multiple attribute value changes 1432 * @param con_handle 1433 * @param num_attributes 1434 * @param attribute_handles[] 1435 * @param values_data[] 1436 * @param values_len[] 1437 * @return 0 if ok, error otherwise 1438 */ 1439 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes, 1440 const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len){ 1441 1442 att_server_t * att_server = NULL; 1443 att_connection_t * att_connection = NULL; 1444 uint8_t * packet_buffer = NULL; 1445 1446 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1447 if (status != ERROR_CODE_SUCCESS){ 1448 return status; 1449 } 1450 1451 uint16_t size = att_prepare_handle_value_multiple_notification(att_connection, num_attributes, attribute_handles, values_data, values_len, packet_buffer); 1452 1453 return att_server_send_prepared(att_server, att_connection, packet_buffer, size); 1454 } 1455 1456 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len){ 1457 1458 att_server_t * att_server = NULL; 1459 att_connection_t * att_connection = NULL; 1460 uint8_t * packet_buffer = NULL; 1461 1462 uint8_t status = att_server_prepare_server_message(con_handle, &att_server, &att_connection, &packet_buffer); 1463 if (status != ERROR_CODE_SUCCESS){ 1464 return status; 1465 } 1466 1467 if (att_server->value_indication_handle != 0u) { 1468 // free reserved packet buffer 1469 if (att_server->bearer_type == ATT_BEARER_ENHANCED_LE){ 1470 l2cap_release_packet_buffer(); 1471 } 1472 return ATT_HANDLE_VALUE_INDICATION_IN_PROGRESS; 1473 } 1474 1475 // track indication 1476 att_server->value_indication_handle = attribute_handle; 1477 btstack_run_loop_set_timer_handler(&att_server->value_indication_timer, att_handle_value_indication_timeout); 1478 btstack_run_loop_set_timer(&att_server->value_indication_timer, ATT_TRANSACTION_TIMEOUT_MS); 1479 btstack_run_loop_add_timer(&att_server->value_indication_timer); 1480 1481 uint16_t size = att_prepare_handle_value_indication(att_connection, attribute_handle, value, value_len, packet_buffer); 1482 1483 return att_server_send_prepared(att_server, att_connection, NULL, size); 1484 } 1485 1486 uint16_t att_server_get_mtu(hci_con_handle_t con_handle){ 1487 hci_connection_t * hci_connection = hci_connection_for_handle(con_handle); 1488 if (!hci_connection) return 0; 1489 att_connection_t * att_connection = &hci_connection->att_connection; 1490 return att_connection->mtu; 1491 } 1492 1493 void att_server_deinit(void){ 1494 att_server_client_read_callback = NULL; 1495 att_server_client_write_callback = NULL; 1496 att_client_packet_handler = NULL; 1497 service_handlers = NULL; 1498 att_server_flags = 0; 1499 } 1500 1501 #ifdef ENABLE_GATT_OVER_EATT 1502 1503 #define MAX_NR_EATT_CHANNELS 5 1504 1505 static uint16_t att_server_eatt_receive_buffer_size; 1506 static uint16_t att_server_eatt_send_buffer_size; 1507 1508 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_cid(uint16_t cid){ 1509 btstack_linked_list_iterator_t it; 1510 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1511 while(btstack_linked_list_iterator_has_next(&it)){ 1512 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1513 if (eatt_bearer->att_server.l2cap_cid == cid) { 1514 return eatt_bearer; 1515 } 1516 } 1517 return NULL; 1518 } 1519 1520 static att_server_eatt_bearer_t * att_server_eatt_bearer_for_con_handle(hci_con_handle_t con_handle){ 1521 btstack_linked_list_iterator_t it; 1522 btstack_linked_list_iterator_init(&it, &att_server_eatt_bearer_active); 1523 while(btstack_linked_list_iterator_has_next(&it)){ 1524 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) btstack_linked_list_iterator_next(&it); 1525 if (eatt_bearer->att_connection.con_handle == con_handle) { 1526 return eatt_bearer; 1527 } 1528 } 1529 return NULL; 1530 } 1531 1532 static void att_server_eatt_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 1533 uint16_t cid; 1534 uint8_t status; 1535 uint16_t remote_mtu; 1536 1537 uint8_t i; 1538 uint8_t num_requested_bearers; 1539 uint8_t num_accepted_bearers; 1540 uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; 1541 uint8_t * receive_buffers[MAX_NR_EATT_CHANNELS]; 1542 uint16_t cids[MAX_NR_EATT_CHANNELS]; 1543 att_server_eatt_bearer_t * eatt_bearers[MAX_NR_EATT_CHANNELS]; 1544 att_server_eatt_bearer_t * eatt_bearer; 1545 att_server_t * att_server; 1546 att_connection_t * att_connection; 1547 hci_con_handle_t con_handle; 1548 hci_connection_t * hci_connection; 1549 1550 switch (packet_type) { 1551 1552 case L2CAP_DATA_PACKET: 1553 eatt_bearer = att_server_eatt_bearer_for_cid(channel); 1554 btstack_assert(eatt_bearer != NULL); 1555 att_server = &eatt_bearer->att_server; 1556 att_connection = &eatt_bearer->att_connection; 1557 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1558 break; 1559 1560 case HCI_EVENT_PACKET: 1561 switch (packet[0]) { 1562 1563 case L2CAP_EVENT_CAN_SEND_NOW: 1564 cid = l2cap_event_packet_sent_get_local_cid(packet); 1565 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1566 btstack_assert(eatt_bearer != NULL); 1567 att_server = &eatt_bearer->att_server; 1568 att_connection = &eatt_bearer->att_connection; 1569 // only used for EATT request responses 1570 btstack_assert(att_server->state == ATT_SERVER_REQUEST_RECEIVED_AND_VALIDATED); 1571 att_server_process_validated_request(att_server, att_connection, eatt_bearer->send_buffer); 1572 break; 1573 1574 case L2CAP_EVENT_PACKET_SENT: 1575 cid = l2cap_event_packet_sent_get_local_cid(packet); 1576 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1577 btstack_assert(eatt_bearer != NULL); 1578 att_server = &eatt_bearer->att_server; 1579 att_connection = &eatt_bearer->att_connection; 1580 att_server_handle_att_pdu(att_server, att_connection, packet, size); 1581 break; 1582 1583 case L2CAP_EVENT_ECBM_INCOMING_CONNECTION: 1584 cid = l2cap_event_ecbm_incoming_connection_get_local_cid(packet); 1585 1586 // reject if outgoing l2cap connection active, L2CAP/TIM/BV-01-C 1587 con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1588 hci_connection = hci_connection_for_handle(con_handle); 1589 btstack_assert(hci_connection != NULL); 1590 if (hci_connection->att_server.eatt_outgoing_active) { 1591 hci_connection->att_server.incoming_connection_request = true; 1592 l2cap_ecbm_decline_channels(cid, L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE ); 1593 log_info("Decline incoming connection from %s", bd_addr_to_str(hci_connection->address)); 1594 } else { 1595 num_requested_bearers = l2cap_event_ecbm_incoming_connection_get_num_channels(packet); 1596 for (i = 0; i < num_requested_bearers; i++){ 1597 eatt_bearers[i] = (att_server_eatt_bearer_t *) btstack_linked_list_pop(&att_server_eatt_bearer_pool); 1598 if (eatt_bearers[i] == NULL) { 1599 break; 1600 } 1601 eatt_bearers[i]->att_connection.con_handle = l2cap_event_ecbm_incoming_connection_get_handle(packet); 1602 eatt_bearers[i]->att_server.bearer_type = ATT_BEARER_ENHANCED_LE; 1603 receive_buffers[i] = eatt_bearers[i]->receive_buffer; 1604 btstack_linked_list_add(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearers[i]); 1605 } 1606 num_accepted_bearers = i; 1607 status = l2cap_ecbm_accept_channels(cid, num_accepted_bearers, initial_credits, att_server_eatt_receive_buffer_size, receive_buffers, cids); 1608 btstack_assert(status == ERROR_CODE_SUCCESS); 1609 log_info("requested %u, accepted %u", num_requested_bearers, num_accepted_bearers); 1610 for (i=0;i<num_accepted_bearers;i++){ 1611 log_info("eatt l2cap cid: 0x%04x", cids[i]); 1612 eatt_bearers[i]->att_server.l2cap_cid = cids[i]; 1613 } 1614 } 1615 break; 1616 1617 case L2CAP_EVENT_ECBM_CHANNEL_OPENED: 1618 cid = l2cap_event_ecbm_channel_opened_get_local_cid(packet); 1619 status = l2cap_event_ecbm_channel_opened_get_status(packet); 1620 remote_mtu = l2cap_event_ecbm_channel_opened_get_remote_mtu(packet); 1621 eatt_bearer = att_server_eatt_bearer_for_cid(cid); 1622 btstack_assert(eatt_bearer != NULL); 1623 eatt_bearer->att_connection.mtu_exchanged = true; 1624 eatt_bearer->att_connection.mtu = remote_mtu; 1625 eatt_bearer->att_connection.max_mtu = remote_mtu; 1626 log_info("L2CAP_EVENT_ECBM_CHANNEL_OPENED - cid 0x%04x mtu %u, status 0x%02x", cid, remote_mtu, status); 1627 break; 1628 1629 case L2CAP_EVENT_ECBM_RECONFIGURED: 1630 break; 1631 1632 case L2CAP_EVENT_CHANNEL_CLOSED: 1633 eatt_bearer = att_server_eatt_bearer_for_cid(l2cap_event_channel_closed_get_local_cid(packet)); 1634 btstack_assert(eatt_bearer != NULL); 1635 1636 // TODO: finalize - abort queued writes 1637 1638 btstack_linked_list_remove(&att_server_eatt_bearer_active, (btstack_linked_item_t *) eatt_bearer); 1639 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1640 break; 1641 default: 1642 break; 1643 } 1644 break; 1645 default: 1646 btstack_unreachable(); 1647 break; 1648 } 1649 } 1650 1651 // create eatt bearers 1652 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size){ 1653 uint16_t size_for_structs = num_eatt_bearers * sizeof(att_server_eatt_bearer_t); 1654 if (storage_size < size_for_structs) { 1655 return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED; 1656 } 1657 1658 // TODO: The minimum ATT_MTU for an Enhanced ATT bearer is 64 octets. 1659 1660 memset(storage_buffer, 0, storage_size); 1661 uint16_t buffer_size_per_bearer = ((storage_size - size_for_structs) / num_eatt_bearers); 1662 att_server_eatt_receive_buffer_size = buffer_size_per_bearer / 2; 1663 att_server_eatt_send_buffer_size = buffer_size_per_bearer / 2; 1664 uint8_t * bearer_buffer = &storage_buffer[size_for_structs]; 1665 uint8_t i; 1666 att_server_eatt_bearer_t * eatt_bearer = (att_server_eatt_bearer_t *) storage_buffer; 1667 log_info("%u EATT bearers with receive buffer size %u", 1668 num_eatt_bearers, att_server_eatt_receive_buffer_size); 1669 for (i=0;i<num_eatt_bearers;i++){ 1670 eatt_bearer->att_connection.con_handle = HCI_CON_HANDLE_INVALID; 1671 eatt_bearer->receive_buffer = bearer_buffer; 1672 bearer_buffer += att_server_eatt_receive_buffer_size; 1673 eatt_bearer->send_buffer = bearer_buffer; 1674 bearer_buffer += att_server_eatt_send_buffer_size; 1675 btstack_linked_list_add(&att_server_eatt_bearer_pool, (btstack_linked_item_t *) eatt_bearer); 1676 eatt_bearer++; 1677 } 1678 // TODO: define minimum EATT MTU 1679 return l2cap_ecbm_register_service(att_server_eatt_handler, BLUETOOTH_PSM_EATT, 64, LEVEL_2, false); 1680 } 1681 #endif 1682